240 PATHOGENIC BACTERIA. presence of a small motile bacillus which could easily be stained by ordinary methods (Fig. 64). When introduced FIG. 64.Bacillus pseudo-tuberculosis from agar-agar; x 1000 (Itzerott and Niemann). subcutaneously into guinea-pigs the original disease was produced. Pseudo-tuberculosis seems to be an indefinite affection of which we have very little knowledge, and which is certainly in no way connected with or related to true tuberculosis.